ruby - Ruby Error: koala no such file to load LoadError

Question

我已经在一台机器上安装了 Ruby（不是 Rails），并试图运行一些基于 Facebook 的 koala 框架的代码。
当我跑

    gem list

提到了考拉，但是当我运行文件时，我收到了这个错误。Rubygems 已经安装，我不知道还能做什么。有任何想法吗？

编辑：

    require 'koala'
    require 'json'

    @graph = Koala::Facebook::API.new("CAACEdEose0cBANb7YuygrBflSkBrpdalb4e70T5lJgdLPYEh0Uxy5JLPVdukKSiwZAK8g27DnwscSUWNaC0s53ogq6h562LETjYO4sB5lZAMAy8tC0SM9UzqXkk7GKYpaLrkQlgj1oLTdOJhBfq5KJtFxZBkOkpz8HaVPLYp66OnuGkaGOogVseR1tUNXVxToKl6ZCmwHL0i5RHNvMnd")




    url = File.open("urls.txt","r")
    url.each_line do |line|
        id = /[\d]+/.match(line)
        begin
            temp = @graph.get_object(id)
            list = File.open("working.txt", "a")
            list.write(id)
            list.write("\n")
            puts "Worked for #{id}."
        rescue
            puts "Didn't work for #{id}."
        end      
    end